Rozhen Observation Calendar

Which nights are best for a target over the coming weeks. The astronomy mark (darkness × altitude × Moon) is computed for every night; the weather and the overall mark exist only where Open-Meteo has a forecast (the next four days) or ERA5 history (past nights) — the rest is honestly blank.

Best nights for Vega: 06-07 (100), 06-08 (100), 06-09 (100), 06-10 (100), 06-11 (100) — by astronomy; check the weather when the night is within four days.

2034-06-03astronomy score per night — click a bar for that night2034-07-02

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2034-06-03 Sat	50	—	unknown	23:00–03:45 (marginal, 4.75 h)	87.1° 03:10	4.72	97%	57.4°
2034-06-04 Sun	58	—	unknown	23:00–01:50 (good, 2.83 h)	87.1° 03:05	4.69	93%	56.9°
2034-06-05 Mon	91	—	unknown	23:00–03:40 (good, 4.67 h)	87.1° 03:00	4.66	87%	58.1°
2034-06-06 Tue	98	—	unknown	23:05–03:40 (good, 4.58 h)	87.1° 02:55	4.63	79%	61.0°
2034-06-07 Wed	100	—	unknown	23:05–03:40 (good, 4.58 h)	87.1° 02:55	4.61	70%	65.4°
2034-06-08 Thu	100	—	unknown	23:05–03:40 (good, 4.58 h)	87.1° 02:50	4.58	60%	71.1°
2034-06-09 Fri	100	—	unknown	23:05–03:40 (good, 4.58 h)	87.1° 02:45	4.56	49%	77.8°
2034-06-10 Sat	100	—	unknown	23:05–03:40 (good, 4.58 h)	87.1° 02:40	4.53	38%	85.2°
2034-06-11 Sun	100	—	unknown	23:10–03:40 (good, 4.5 h)	87.1° 02:40	4.51	27%	93.0°
2034-06-12 Mon	100	—	unknown	23:10–03:40 (good, 4.5 h)	87.1° 02:35	4.5	17%	100.8°
2034-06-13 Tue	100	—	unknown	23:10–03:40 (good, 4.5 h)	87.1° 02:30	4.48	9%	108.2°
2034-06-14 Wed	100	—	unknown	23:10–03:40 (good, 4.5 h)	87.1° 02:25	4.47	4%	114.7°
2034-06-15 Thu	100	—	unknown	23:10–03:40 (good, 4.5 h)	87.1° 02:20	4.45	1%	119.6°
2034-06-16 Fri	100	—	unknown	23:10–03:40 (good, 4.5 h)	87.1° 02:20	4.44	0%	122.5°
2034-06-17 Sat	100	—	unknown	23:10–03:40 (good, 4.5 h)	87.1° 02:15	4.43	3%	123.0°
2034-06-18 Sun	100	—	unknown	23:10–03:40 (good, 4.5 h)	87.1° 02:10	4.43	9%	121.2°
2034-06-19 Mon	100	—	unknown	23:10–03:40 (good, 4.5 h)	87.1° 02:05	4.42	16%	117.5°
2034-06-20 Tue	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.1° 02:00	4.42	24%	112.5°
2034-06-21 Wed	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.1° 02:00	4.42	34%	106.6°
2034-06-22 Thu	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.1° 01:55	4.43	43%	100.3°
2034-06-23 Fri	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.1° 01:50	4.43	53%	93.7°
2034-06-24 Sat	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.1° 01:45	4.44	63%	87.2°
2034-06-25 Sun	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.1° 01:45	4.45	72%	80.8°
2034-06-26 Mon	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.1° 01:40	4.46	80%	74.7°
2034-06-27 Tue	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.1° 01:35	4.47	87%	69.1°
2034-06-28 Wed	67	—	unknown	23:15–03:40 (good, 4.42 h)	87.1° 01:30	4.48	92%	64.2°
2034-06-29 Thu	57	—	unknown	01:45–03:40 (good, 1.92 h)	87.1° 01:25	4.5	97%	60.4°
2034-06-30 Fri	50	—	unknown	03:20–03:45 (good, 0.42 h)	87.1° 01:25	4.52	99%	57.9°
2034-07-01 Sat	47	—	unknown	23:10–03:45 (marginal, 4.58 h)	87.1° 01:20	4.54	100%	56.9°
2034-07-02 Sun	50	—	unknown	23:10–23:45 (good, 0.58 h)	87.1° 01:15	4.56	98%	57.8°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2034-06-03&days=30"
curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&days=30&format=csv" -o m31-calendar.csv

One row per night: score_astronomy always, score_weather / score only where a forecast or history exists (null otherwise, with weather_source saying which), best window, dark hours, Moon illumination and separation, transit. 7–60 nights. Errors: 400 with invalid_date or target_unresolved. Results are cached for six hours; calculation version 2026-10-10.1.